Spatial and temporal variations of suspended sediment responses from the subtropical Richmond River catchment, NSW, Australia

Soil Research ◽  
2002 ◽  
Vol 40 (3) ◽  
pp. 419 ◽  
Author(s):  
Shahadat Hossain ◽  
Bradley Eyre ◽  
David McConchie
Keyword(s):  
Suspended Sediment ◽  
Sediment Load ◽  
Land Use Changes ◽  
Suspended Sediments ◽  
Temporal Variations ◽  
Suspended Sediment Load ◽  
Flood Events ◽  
River Catchment ◽  
Forest Coverage ◽  
Dry Seasons

Suspended sediment exports from the Richmond River catchment were examined during 2 hydrological years (1994–96). On a yearly basis, the Richmond River catchment produced <2% suspended sediment load during dry seasons, whereas about 75–91% of the yearly suspended sediments were exported during floods which occurred <5% of the year. Annual suspended sediment exports from the Richmond River catchment varied more than 7-fold from dry year to wet year. Among the 3 major subcatchments, Richmond and Wilsons River subcatchments generated >93% of the suspended sediment load, while sediment exports from the Bungawalbin Creek subcatchment always remained low due to its flat topography and extensive forest coverage. Suspended sediment hysteresis patterns exhibited a clockwise response for 2 steep and less forested subcatchments and an anti-clockwise response for relatively low gradient and more forested subcatchment during all flood events. Land use changes in the Richmond River subcatchments indicate a possible increase of suspended sediment load of about 6-fold from their pristine condition.

scholarly journals Sub-Bankfull Flow Frequency versus Magnitude of Flood Events in Outlining Effective Discharges. Case Study: Trotuș River (Romania)

2018 ◽  
Author(s):  
Dan Dumitriu
Keyword(s):  
Suspended Sediment ◽  
Sediment Load ◽  
Temporal Variations ◽  
Data Series ◽  
Suspended Sediment Transport ◽  
Suspended Sediment Load ◽  
Flood Events ◽  
Effective Discharge ◽  
Bankfull Discharge

Effective discharge, which represents the flow, or range of flows, that transport the most sediment over long term, was determined based on the mean daily flow discharge and mean daily suspended sediment discharge recorded between 1994 and 2014 at four gauging stations along the Trotuș River. This study proposes an efficient method for the estimation of effective discharge based on observed values of the suspended sediment load. By employing this method the suspended sediment load is no longer either under- or overestimated as in the cases when the assessment is based on sediment rating curves. The assessment on effective discharge was performed at two distinct levels: for the entire data series during the investigated time spans and, subsequently, for flows less than the bankfull discharge. The effectiveness curves of the suspended sediment transport characteristics revealed highly multimodal characteristics with many peaks, indicating ample ranges for the effective discharges. The main effective discharge corresponded to large flood events, which are typical for the upper end of the discharge range, whereas the secondary effective discharges corresponded to sub-bankfull flows, which are more frequent. The changes that occurred in the channel bed are reflected by the temporal variations in the effective discharge.

scholarly journals Sub-Bankfull Flow Frequency versus Magnitude of Flood Events in Outlining Effective Discharges. Case Study: Trotuș River (Romania)

Water ◽  
2018 ◽  
Vol 10 (10) ◽  
pp. 1292 ◽  
Author(s):  
Dan Dumitriu
Keyword(s):  
Suspended Sediment ◽  
Sediment Load ◽  
Temporal Variations ◽  
Data Series ◽  
Suspended Sediment Transport ◽  
Suspended Sediment Load ◽  
Flood Events ◽  
Effective Discharge ◽  
Bankfull Discharge

Effective discharge, which represents the flow, or range of flows, that transport the most sediment over the long-term, was determined based on the mean daily flow discharge and mean daily suspended sediment discharge recorded between 1994 and 2014 at four gauging stations along the Trotuș River. This study proposes an efficient method for the estimation of effective discharge based on observed values of the suspended sediment load. By employing this method the suspended sediment load is no longer either under- or overestimated as in the cases when the assessment is based on sediment rating curves. The assessment on effective discharge was performed at two distinct levels: for the entire data series during the investigated time spans and, subsequently, for flows less than the bankfull discharge. The effectiveness curves of the suspended sediment transport characteristics revealed highly multimodal characteristics with many peaks, indicating ample ranges for the effective discharges. The main effective discharge corresponded to large flood events, which are typical for the upper end of the discharge range, whereas the secondary effective discharges corresponded to sub-bankfull flows, which are more frequent. The changes that occurred in the channel bed are reflected by the temporal variations in the effective discharge.

Determining Sub-Catchment Contributions to the Suspended Sediment load of the Tsitsa River, Eastern Cape, South Africa

2020 ◽  
Author(s):  
Laura Bannatyne ◽  
Ian Foster ◽  
Ian Meiklejohn ◽  
Bennie van der Waal
Keyword(s):  
South Africa ◽  
Developing Countries ◽  
Suspended Sediment ◽  
Sediment Load ◽  
Fine Sediment ◽  
Eastern Cape Province ◽  
Suspended Sediment Load ◽  
Eastern Cape ◽  
Catchment Scale ◽  
River Catchment

&lt;p&gt;In South Africa, as in many developing countries, the suspended sediment (SS) data required to support catchment scale hillslope restoration and rehabilitation programmes are typically scarce or absent, leading to a reliance on modelled SS loads and yields that are generally not validated by measured SS data. An exception is the Tsitsa River catchment in the Eastern Cape Province, where modelled SS yields were high (21 &amp;#8211; 50 t/ha/yr), leading to the establishment of a Citizen Technician-based monitoring programme (2015 &amp;#8211; 2019) that has provided flood-focused, sub-catchment scale SS data at sub-daily timestep for 11 sites throughout the 4000 km&lt;sup&gt;2&lt;/sup&gt; catchment.&lt;/p&gt;&lt;p&gt;A confluence-based SS fingerprinting and tracing exercise was undertaken in the catchment (2018). Analysis of the distinctive physicochemical properties of resuspended fine sediment sampled above and below major confluences allowed the percentage of SS contributed by each tributary to be apportioned, and compared with findings from both the SS monitoring campaign and from existing models.&lt;/p&gt;

scholarly journals Predicting suspended sediment load in Peninsular Malaysia using support vector machine and deep learning algorithms

2022 ◽  
Vol 12 (1) ◽  
Author(s):  
Yusuf Essam ◽  
Yuk Feng Huang ◽  
Ahmed H. Birima ◽  
Ali Najah Ahmed ◽  
Ahmed El-Shafie
Keyword(s):  
Support Vector Machine ◽  
Suspended Sediment ◽  
Sediment Load ◽  
Short Term Memory ◽  
Suspended Sediments ◽  
Peninsular Malaysia ◽  
Support Vector ◽  
Data Sets ◽  
Suspended Sediment Load ◽  
Data Set

AbstractHigh loads of suspended sediments in rivers are known to cause detrimental effects to potable water sources, river water quality, irrigation activities, and dam or reservoir operations. For this reason, the study of suspended sediment load (SSL) prediction is important for monitoring and damage mitigation purposes. The present study tests and develops machine learning (ML) models, based on the support vector machine (SVM), artificial neural network (ANN) and long short-term memory (LSTM) algorithms, to predict SSL based on 11 different river data sets comprising of streamflow (SF) and SSL data obtained from the Malaysian Department of Irrigation and Drainage. The main objective of the present study is to propose a single model that is capable of accurately predicting SSLs for any river data set within Peninsular Malaysia. The ANN3 model, based on the ANN algorithm and input scenario 3 (inputs consisting of current-day SF, previous-day SF, and previous-day SSL), is determined as the best model in the present study as it produced the best predictive performance for 5 out of 11 of the tested data sets and obtained the highest average RM with a score of 2.64 when compared to the other tested models, indicating that it has the highest reliability to produce relatively high-accuracy SSL predictions for different data sets. Therefore, the ANN3 model is proposed as a universal model for the prediction of SSL within Peninsular Malaysia.

scholarly journals A new approach to the calculation of the greatest debit of suspended mud flood load considering influence of main natural factors (by the sample of rivers of Minor Caucauses)

2020 ◽  
Vol 10 ◽  
pp. 31-37
Author(s):  
J. H. Mamedov ◽  
◽  
Z. R. Rasulov
Keyword(s):  
Suspended Sediment ◽  
Forest Cover ◽  
River Flow ◽  
Sediment Load ◽  
Water Discharge ◽  
Suspended Sediments ◽  
Calculation Error ◽  
Suspended Sediment Load ◽  
Flow Rates ◽  
Natural Factors

The work is devoted to the methodology for calculating the highest flow rates of suspended sediment mudflows of the rivers of the Minor Caucasus. The research materials were the data from stationary observations of the highest suspended sediment load presented by the Department of Hydrometeorology under the Ministry of Natural Resources of the Republic of Azerbaijan until 2000 and data from expeditionary operations until 2016. For extension of the series of the highest suspended sediment load rates, the relationships Qmax. = f (Rvax.) from 2000 to 2015. The parameters of physical and geographic factors influencing the high flow rates of suspended sediments are analyzed separately and in a complex. As main natural factors that determine the volume of mudflow sediment load, the values of the highest water discharge, the coefficient of natural regulation of river flow and forest cover of the catchment area were taken. The study resulted in the methodology for calculating the largest flow rate of suspended sediment. It mostly reflects conditions for the formation of mudflows and has a calculation error of ± 25%. Recommended formulas can be used to study and describe parameters of mudflows of unexplored rivers of the Minor Caucasus.

scholarly journals Balance sedimentario del embalse de Ribarroja

2021 ◽  
Author(s):  
A. Tena ◽  
D. Vericat ◽  
R.J. Batalla
Keyword(s):  
Suspended Sediment ◽  
Sediment Load ◽  
Land Use Changes ◽  
Suspended Sediment Transport ◽  
Suspended Sediment Load ◽  
Lower Reach ◽  
Iberian Range ◽  
Intermittent Rivers ◽  
Sediment Transfer

The aim of this study was to build up a sediment budget of the Ribarroja Reservoir, which is located in the lower reach of the River Ebro. For this purpose, we analysed continuous discharge and suspended sediment transport data at several river sections entering the reservoir and at the dam outlet, for the period 2008-2011. The sediment load estimated upstream of the Mequinenza reservoir was 0.66×106 t a-1, whereas the estimated output was 0.04×106 t a-1. The sediment input coming from the large but highly regulated Pyrenean tributaries (Segre and Cinca) was 0.16×106 t a-1, whereas intermittent rivers naturally flowing from the Iberian Range (Matarraña and Algars) supplied an average load of 760 t a-1. The suspended sediment load trapped in the Mequinenza and Ribarroja reservoirs for the study period was estimated at 0.78×106 t a-1, which implies a reduction of ca. 95% of the sediment load of the river. The results illustrate the role of reservoirs in interrupting the sediment transfer in the lower reach of the Ebro, within a context of structural sediment deficit, following widespread land use changes (afforestation) that took place in the catchment after the 1940s.

scholarly journals Suspended Sediment Load Simulation during Flood Events Using Intelligent Systems: A Case Study on Semiarid Regions of Mediterranean Basin

Water ◽  
2021 ◽  
Vol 13 (24) ◽  
pp. 3539
Author(s):  
Zaki Abda ◽  
Bilel Zerouali ◽  
Muwaffaq Alqurashi ◽  
Mohamed Chettih ◽  
Celso Augusto Guimarães Santos ◽  
...  
Keyword(s):  
Particle Swarm Optimization ◽  
Suspended Sediment ◽  
Intelligent Systems ◽  
Sediment Load ◽  
Particle Swarm ◽  
Natural Phenomenon ◽  
Suspended Sediment Load ◽  
Flood Events ◽  
Swarm Optimization ◽  
Inference System

Sediment transport in rivers is a nonlinear natural phenomenon, which can harm the environment and hydraulic structures and is one of the main reasons for the dams’ siltation. In this paper, the following artificial intelligence approaches were used to simulate the suspended sediment load (SSL) during periods of flood events in the northeastern Algerian river basins: artificial neural network combined with particle swarm optimization (ANN-PSO), adaptive neuro-fuzzy inference system combined with particle swarm optimization (ANFIS-PSO), random forest (RF), and long short-term memory (LSTM). The comparison of the prediction accuracies of such different intelligent system approaches revealed that ANN-PSO, RF, and LSTM satisfactorily simulated the nonlinear process of SSL. Carefully comparing the results, the ANN-PSO model showed a slight superiority over the RF and LSTM models, with RMSE = 67.2990 kg/s in the Chemourah basin and RMSE = 55.8737 kg/s in the Gareat el tarf basin.

scholarly journals Land-Use/-Cover Changes and Their Effect on Soil Erosion and River Suspended Sediment Load in Different Landscape Zones of European Russia during 1970–2017

Water ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 1631
Author(s):  
Artyom V. Gusarov
Keyword(s):  
Soviet Union ◽  
Suspended Sediment ◽  
Sediment Load ◽  
Gully Erosion ◽  
European Russia ◽  
Relative Reduction ◽  
Forest Steppe ◽  
Suspended Sediment Load ◽  
Cultivated Land ◽  
Study Region

Contemporary trends in cultivated land and their influence on soil/gully erosion and river suspended sediment load were analyzed by various landscape zones within the most populated and agriculturally developed part of European Russia, covering 2,222,390 km2. Based on official statistics from the Russian Federation and the former Soviet Union, this study showed that after the collapse of the Soviet Union in 1991, there was a steady downward trend in cultivated land throughout the study region. From 1970–1987 to 2005–2017, the region lost about 39% of its croplands. Moreover, the most significant relative reduction in cultivated land was noted in the forest zone (south taiga, mixed and broadleaf forests) and the dry steppes and the semi-desert of the Caspian Lowland—about 53% and 65%, respectively. These territories are with climatically risky agriculture and less fertile soils. There was also a widespread reduction in agricultural machinery on croplands and livestock on pastures of the region. A decrease in soil/gully erosion rates over the past decades was also revealed based on state hydrological monitoring data on river suspended sediment load as one of the indicators of the temporal variability of erosion intensity in river basins and the published results of some field research in various parts of the studied landscape zones. The most significant reduction in the intensity of erosion and the load of river suspended sediment was found in European Russia’s forest-steppe zone. This was presumably due to a favorable combination of the above changes in land cover/use and climate change.

Sign in / Sign up

Export Citation Format

Share Document